Semiconductor device having an oxygen diffusion barrier

Abstract

A semiconductor device includes a semiconductor body having opposite first and second surfaces, a drift or base zone in the semiconductor body and an oxygen diffusion barrier in the semiconductor body. The drift or base zone is located between the first surface and the oxygen diffusion barrier and directly adjoins the oxygen diffusion barrier. The semiconductor device further includes first and second load terminal contacts. At least one of the first and the second load terminal contacts is electrically connected to the semiconductor body through the first surface.

What is claimed is: 
     
       1. A semiconductor device, comprising:
 a semiconductor body comprising opposite first and second surfaces; 
 a drift or base zone in the semiconductor body; 
 an oxygen diffusion barrier comprising SiGe and formed in the semiconductor body, wherein the drift or base zone is located between the first surface and the oxygen diffusion barrier and directly adjoins the oxygen diffusion barrier; and 
 first and second load terminal contacts, wherein at least one of the first and the second load terminal contacts is electrically connected to the semiconductor body through the first surface. 
 
     
     
       2. The semiconductor device of  claim 1 , wherein the semiconductor body further comprises a Czochralski or magnetic Czochralski silicon substrate between the second surface of the semiconductor body and the oxygen diffusion barrier. 
     
     
       3. The semiconductor device of  claim 1 , wherein a maximum Ge content in the oxygen diffusion barrier ranges from 1% to 40%. 
     
     
       4. The semiconductor device of  claim 1 , wherein a thickness of the oxygen diffusion barrier ranges from 0.2 μm to 2 μm. 
     
     
       5. The semiconductor device of  claim 1 , wherein a Ge content in the oxygen diffusion barrier increases continuously or stepwise towards the first surface of the semiconductor body. 
     
     
       6. The semiconductor device of  claim 1 , wherein a Ge content in the oxygen diffusion barrier decreases continuously or stepwise towards the first surface of the semiconductor body. 
     
     
       7. The semiconductor device of  claim 1 , wherein a Ge content in the oxygen diffusion barrier increases continuously or stepwise in a first part, is constant in a second part, and decreases continuously or stepwise in a third part towards the first surface of the semiconductor body. 
     
     
       8. The semiconductor device of  claim 1 , wherein the oxygen diffusion barrier is a superlattice comprising SiGe and Si layers. 
     
     
       9. The semiconductor device of  claim 1 , wherein the oxygen diffusion barrier further comprises carbon. 
     
     
       10. The semiconductor device of  claim 1 , wherein the semiconductor body comprises a semiconductor layer, wherein the drift or base zone is part of or corresponds to the silicon layer, and wherein a thickness of the silicon layer is set to a value between 40 μm and 200 μm. 
     
     
       11. The semiconductor device of  claim 1 , wherein the semiconductor device is one device of a power semiconductor diode, a power insulated gate bipolar transistor, a power bipolar junction transistor, a power silicon controlled rectifier, and a power insulated gate field effect transistor. 
     
     
       12. The semiconductor device of  claim 11 , wherein the semiconductor device is a vertical power semiconductor device comprising the first load terminal contact at a first surface of the semiconductor body and second load terminal contact at the second surface of the semiconductor body, and further comprising an edge termination structure at the first surface of the semiconductor body surrounding an active area of the semiconductor device. 
     
     
       13. The semiconductor device of  claim 1 , wherein the semiconductor body further comprises an n-doped region comprising hydrogen-related donors. 
     
     
       14. The semiconductor device of  claim 1 , wherein the oxygen diffusion barrier is one of an n-doped diode emitter region, an n-doped drain region, and a p-doped emitter region. 
     
     
       15. The semiconductor device of  claim 1 , wherein an oxygen concentration in the oxygen diffusion barrier is in a range of 5×10 16  cm −3  and 1×10 18  cm −3 . 
     
     
       16. A semiconductor device, comprising:
 a semiconductor body comprising opposite first and second surfaces; 
 a drift or base zone in the semiconductor body; 
 an oxygen diffusion barrier in the semiconductor body, wherein the drift or base zone is located between the first surface and the oxygen diffusion barrier and directly adjoins the oxygen diffusion barrier; and 
 first and second load terminal contacts, wherein at least one of the first and the second load terminal contacts is electrically connected to the semiconductor body through the first surface, 
 wherein the semiconductor body further comprises a Czochralski or magnetic Czochralski silicon substrate between the second surface of the semiconductor body and the oxygen diffusion barrier. 
 
     
     
       17. The semiconductor device of  claim 16 , wherein the oxygen diffusion barrier comprises SiGe. 
     
     
       18. A semiconductor device, comprising:
 a semiconductor body comprising opposite first and second surfaces; 
 a drift or base zone in the semiconductor body; 
 an oxygen diffusion barrier in the semiconductor body, wherein the drift or base zone is located between the first surface and the oxygen diffusion barrier and directly adjoins the oxygen diffusion barrier; and 
 first and second load terminal contacts, wherein at least one of the first and the second load terminal contacts is electrically connected to the semiconductor body through the first surface, 
 wherein the semiconductor body further comprises an n-doped region comprising hydrogen-related donors. 
 
     
     
       19. The semiconductor device of  claim 18 , wherein the oxygen diffusion barrier comprises SiGe. 
     
     
       20. A semiconductor device, comprising:
 a semiconductor body comprising opposite first and second surfaces; 
 a drift or base zone in the semiconductor body; 
 an oxygen diffusion barrier in the semiconductor body, wherein the drift or base zone is located between the first surface and the oxygen diffusion barrier and directly adjoins the oxygen diffusion barrier; and 
 first and second load terminal contacts, wherein at least one of the first and the second load terminal contacts is electrically connected to the semiconductor body through the first surface, 
 wherein an oxygen concentration in the oxygen diffusion barrier is in a range of 5×10 16  cm −3  and 1×10 18  cm −3 . 
 
     
     
       21. The semiconductor device of  claim 20 , wherein the oxygen diffusion barrier comprises SiGe.